Hi! I'm not sure you know, but gtk3 flavor can use Webkit2GTK as web browser engine, plist doesn't change, here is a diff for 26.1 port Makefile:
--- Makefile.orig Sun Jun 3 23:29:36 2018 +++ Makefile Mon Jun 4 00:13:09 2018 @@ -79,14 +79,17 @@ WANTLIB += freetype fribidi gdk-x11-2.0 gdk_pixbuf-2.0 WANTLIB += glib-2.0 gobject-2.0 gtk-x11-2.0 intl jpeg lcms2 pango-1.0 WANTLIB += pangocairo-1.0 pangoft2-1.0 png rsvg-2 tiff xcb . elif ${FLAVOR} == "gtk3" -CONFIGURE_ARGS+= --with-x-toolkit=gtk3 -LIB_DEPENDS+= x11/gtk+3 +CONFIGURE_ARGS+= --with-x-toolkit=gtk3 \ + --with-xwidgets +LIB_DEPENDS+= www/webkitgtk4 \ + x11/gtk+3 WANTLIB += ICE MagickCore-6.Q16 MagickWand-6.Q16 SM X11 X11-xcb -WANTLIB += Xext Xfixes Xft Xinerama Xpm Xrandr Xrender atk-1.0 -WANTLIB += cairo cairo-gobject dbus-1 fontconfig freetype fribidi -WANTLIB += gdk-3 gdk_pixbuf-2.0 gif gio-2.0 glib-2.0 gobject-2.0 -WANTLIB += gtk-3 intl jpeg lcms2 pango-1.0 pangocairo-1.0 png -WANTLIB += rsvg-2 tiff xcb +WANTLIB += Xcomposite Xext Xfixes Xft Xinerama Xpm Xrandr Xrender +WANTLIB += atk-1.0 cairo cairo-gobject dbus-1 fontconfig freetype +WANTLIB += fribidi gdk-3 gdk_pixbuf-2.0 gif gio-2.0 glib-2.0 gobject-2.0 +WANTLIB += gtk-3 intl javascriptcoregtk-4.0 jpeg lcms2 pango-1.0 +WANTLIB += pangocairo-1.0 png rsvg-2 soup-2.4 tiff webkit2gtk-4.0 +WANTLIB += xcb . else ERRORS+= "Fatal: Conflicting flavor: ${FLAVOR}" . endif